经济学人 | Japan's monetary policy 日本的货币政策（2

【背景】周三公布的数据显示，日本央行1月份购买了创数据纪录的23.69万亿日元(约合1820亿美元)的国债，突显出该行捍卫收益率上限的决心，以让其不受押注’央行会在短期内加息‘的投资者的攻击。去年12月，日本央行决定扩大围绕10年期国债收益率目标设定的区间，这加剧了市场对它将在近期加息的预期，并迫使日本央行加大债券购买力度，以捍卫新设定的10年期国债收益率0.5%的上限。

Changing the helmsman halfway through a tricky manoeuvre at sea is a risky prospect. Yet that is what is happening in Japan, where the government will soon propose a successor to Kuroda Haruhiko as the head of the Bank of Japan, just as the central bank prepares to tighten monetary policy for the first time since 2007. In December, amid rising inflation and speculative pressure, the bank raised its cap on ten-year government-bond yields, from 0.25% to 0.5%. The next governor is expected to raise the cap further, or even to abandon the policy, which is known as yield-curve control.

【背景】"收紧货币政策"也称紧缩的货币政策，是指央行收紧市场上货币的供应量，使市场资金利率提升的行为。货币政策收紧是为了防止经济过热出现泡沫，防止出现物价大幅上涨通货膨胀，使得市场上货币的总需求和总供给趋于均衡。此外货币政策紧缩还会影响资本市场，使股票等资本市场短期出现下跌。”

在海上进行一次棘手的操作时，中途更换舵手是一种危险的前景。然而，这正是日本正在发生的事情。在日本央行准备收紧货币政策（2007年以来第一次）之际，日本政府将很快提名一位接替黑田东彦出任日本央行行长的人选。去年12月，在不断上升的通货膨胀和投机压力下，央行将十年期政府债券收益率上限从0.25%提高到0.5%。预计下任行长将进一步提高上限，甚至放弃这种被称为"收益率曲线控制"的政策。

Unfortunately, the regime change is not off to a good start. Lifting the cap has only increased bets against it. Since December the Bank of Japan has had to defend the higher cap by buying bonds worth a staggering $240bn, nearly 6% of Japan’s gdp and about three times the pace of purchases in the preceding three months. The bank seems determined to keep the cap in place until a change of leadership is complete. Doing so is a costly mistake. It should change course now.

不幸的是，"管理体制"更迭的开端并不好。取消上限只会增加对它的押注。自去年12月以来，日本央行不得不通过购买价值惊人的2400亿美元的债券来捍卫更高的上限，这一金额几乎是日本GDP的6%，大约是前三个月购买速度的三倍。该央行似乎决心在领导层换届完成之前保持这一上限。这样做是错误的，而且代价高昂。它应该现在改变路线。

Yield-curve control has been the most awkward part of the monetary-policy toolkit developed after the global financial crisis of 2007-09. Having run out of space to cut short-term interest rates, central banks tried to drive down long-term bond yields instead. To that end, they bought bonds with newly created money. By 2016, however, the Bank of Japan’s balance-sheet was ballooning, and it introduced a yield cap in the hope of keeping yields low while making fewer purchases. The idea was that yields would adjust purely on the expectation that the central bank would act if necessary to enforce the cap. And for a time, the policy worked as intended.

在2007-2009年全球金融危机之后，收益率曲线控制一直是货币政策工具箱中最棘手的部分。由于削减短期利率的空间已经用尽，各国央行转而试图压低长期债券收益率。为此，他们用新发行的货币购买债券。然而，到2016年，日本央行的资产负债表急剧膨胀，它引入了收益率上限，希望在减少购买的同时保持低收益率。当时的想法是，收益率将纯粹根据央行在必要时采取行动实施上限的预期进行调整。在一段时间内，该政策起到了预期的效果。

As inflation has risen, however, such caps have lost their credibility. In 2021 Australia suddenly abandoned its experiment with yield-curve control as investors began betting that interest rates would need to rise to fight inflation.

然而，随着通货膨胀的上升，这种上限已经失去了可信度。2021年，澳大利亚突然放弃了其收益率曲线控制的尝试，因为投资者开始押注利率将需要上调以对抗通胀。

In Japan the situation is more finely poised, because inflation has been too low for decades and ongoing stimulus may be necessary to ensure the Bank of Japan hits its 2% inflation target over the next few years. But Japan’s policy is far more aggressive than Australia’s, which capped bonds at a three-year, rather than a ten-year, horizon. A small change in the outlook for the next decade is enough to bring a ten-year cap under pressure.

日本的情况更为稳定，因为几十年来通胀一直过低，为了确保日本央行在未来几年达到2%的通胀目标，持续的刺激措施可能是必要的。但日本的政策远比澳大利亚激进，澳大利亚将债券期限限制在3年期，而非10年期。未来十年前景的一个小变化就足以使十年上限面临压力。

Investors know that Mr Kuroda’s successor is likely to adjust and eventually abandon the policy—especially if it is a hawk, such as Yamaguchi Hirohide, a former deputy governor. The result has been rampant speculation, forcing the bank to hoover up more bonds: exactly what yield-curve control was supposed to avoid. The bank now owns more than half the Japanese government-bond market, including two-thirds of bonds with a maturity between one and 11 years. Bizarrely, its accounts imply that it owns more than 100% of the issuance of some bonds, having lent out its purchases only to buy them back again.

投资者知道黑田东彦的继任者很可能会调整并最终放弃该政策——尤其是如果继任者是鹰派，比如前副行长山口广秀。其结果是投机活动猖獗，迫使银行吸收更多债券: 这正是收益率曲线控制应该避免的。日本央行目前持有日本政府债券市场一半以上的份额，其中三分之二的债券期限在1年至11年之间。奇怪的是，它的账目表明它拥有部分债券发行量的100%以上，借出所购买的债券只是为了再买回来。

For investors, selling bonds to the bank seems a one-way bet. Yields move inversely to prices. Why own a bond that will fall in value as the cap is lifted, if you can sell it for a higher price today? But for the Bank of Japan the purchases could prove correspondingly costly. We calculate that a rise in bond yields of just 0.25 percentage points would cause paper losses of over $60bn. The bank’s cash flows will suffer if short-term rates rise before the bonds mature, forcing the bank to pay interest on the reserves it has created in the banking system to finance its purchases. With every bond bought, the potential loss mounts.

对投资者来说，向该行出售债券似乎是一种单向押注。收益率与价格成反比。如果你现在就能以更高的价格出售，为什么还要持有随着上限取消而贬值的债券呢? 但对日本央行来说，购买债券的代价可能会相应很高。根据我们的计算，债券收益率仅上升0.25个百分点，就会造成逾600亿美元的账面损失。如果短期利率在债券到期前上升，银行的现金流将受到影响，这将迫使银行为购买债券而在银行体系中创造的准备金支付利息。每购买一笔债券，潜在的损失就会增加。

Some argue that the yield cap must be maintained until after wage negotiations in the spring, so that it stimulates average pay rises high enough to be consistent with price growth of 2%, ensuring Japan’s escape from decades of low inflation. But the limited extra stimulus brought about by the cap is not worth the possible losses, which pose a threat to taxpayers. Instead, the central bank’s most important tool is its short-term interest rate, which it can still pledge to keep low to act as a stimulus.

一些人认为，收益率上限必须维持到春季工资谈判结束后，以便刺激平均工资增长，使其足以与2% 的物价增长保持一致，确保日本摆脱数十年的低通胀。但是，上限带来的有限的额外刺激抵不了可能的损失，这对纳税人构成了威胁。相反，央行最重要的工具是其短期利率，它仍然可以承诺维持在低位，以起到刺激作用。

Signalling the end of a price peg is unwise, because it attracts speculation and forces a messy exit. It is too late to avoid that. Everyone knows that the end of yield-curve control is coming in Japan. The central bank—whoever is at its helm—can at least kill off the policy before it loses a lot more money.

发出结束钉住价格的信号是不明智的，因为这会吸引投机，并迫使混乱的退出。现在要避免已经太晚了。每个人都知道，收益率曲线控制在日本即将结束。日本银行——不管是谁掌舵——至少可以在它损失更多的钱之前终止这项政策。